How to cultivate mandarin fish? What are the key points of disease control techniques?

Mandarin fish, also known as osmanthus fish, is a valuable fish in fresh water. Mandarin fish culture has developed rapidly in recent years, which has played an important role in increasing fishery efficiency and fishermen's income, so how to cultivate mandarin fish? What are the key points of disease control techniques?

First, how to cultivate mandarin fish?

1. Set up the hatching ring road

The ring road is a special water body, which simulates the natural ecological conditions and makes the fish eggs tumble continuously. The direct use of loop cultivation of fish fry provides the living environment needed for mandarin fry, and more importantly, when the mandarin fry is fed, it is more important to feed palatable bait fish-other live fry soon after detachment, which can not only meet the nutrition needed for the growth and development of mandarin fry, but also maintain fresh water quality.

2. The choice of parent fish

There are 9 species of mandarin fish in China, such as Siniperca chuatsi, Siniperca chuatsi, Siniperca chuatsi and Siniperca chuatsi.

Mandarin fish like to spawn in running water, artificial breeding first choose 1-2kg healthy and disease-free parent fish pond to raise, when fed with wild miscellaneous fish or commercial feed, artificial spawning can be carried out, injection of carp pituitary or HCG, LRH-An and other hormones, let it naturally ovulate.

3. Raising seedlings in net cage

Mandarin fish eggs are slightly sticky, the specific gravity is larger than water, and it is easy to sink to the bottom. Hatching in the loop should increase the flow rate, not less than 0.2 meters per second. Fish fry can be hatched after 3-4 days of fertilized eggs. More fish fry can be obtained by artificial insemination. Natural fish fry can also be farmed.

Cage is an ideal place for mandarin seedling cultivation. It can not only ensure that there is sufficient and readily available bait, but also have fresh water for continuous exchange. The deficiency is that it can not feed the feed fish which has just taken off the film and needs to wash the box frequently and change the cage regularly. The management of fish fry is more tedious and the operation is more difficult.

The three-stage seedling raising method is generally adopted in the cage:

Class I box, made of 40-28 mesh / 3 cm ethylene mesh, 4-6 m long, 1 m wide and 1 m deep.

II case, sewn with 0.3cm warp knitted ethylene mesh, 2m long, 1m wide and 1m deep.

The III case is made of 0.5cm warp knitted ethylene mesh. It is 2m long, 1m wide and 1m deep.

The matching ratio of the area of I, II and III cages is LRV 10 / 20.

4. Daily feeding

In the early stage, the main food fish was natural breeding allogynogenetic crucian carp, and in the middle and later stage, the main food fish was farmed Meriga dace, with an area ratio of 1 ∶ 3.

2. Technical points of disease control in mandarin fish culture.

1. White spot disease

The cause is caused by the parasite of small melon insects. The specific symptoms are that when a large number of fish are parasitized, white spots appear on the fin and body surface of the diseased fish. Due to stimulation, the infected fish secrete a large amount of mucus on the body surface and Gill, and the fish die because of breathing difficulties.

Prevention and control methods:

(1) soak the fish fry with 150ml / m3 formalin for 10 minutes for 15 minutes.

(2) use formalin splash pond, the concentration is 150.25ml / m3, fully oxygenate during treatment, change clean water and oxygenate immediately after treatment. Pay attention to the small melon disease must not be treated with copper sulfate or salt, these drugs not only can not kill the small melon insects, but will cause the small melon insects to form cysts, thus carrying out mass reproduction and worsening the disease.

2. Ring disease

Is caused by the parasitism of ring worms. The specific symptoms are slow swimming of floating head, blackening of body color, significant edema of Gill, opening of Gill cover, reddish Gill filament and more mucus, and bacterial Gill rot disease is more prevalent in summer and autumn.

Prevention and control methods:

Sprinkle the whole pool with 0.15g / m ~ 2 strong insecticidal essence, apply it again every other day, then add 20cm fresh water, and then sprinkle it with 0.75g / m ~ 2 bleach in the whole pool to prevent and cure Gill rot caused by insect damage.

3. Key points of prevention and control

(1) disinfection should be done well before fish restocking.

(2) stocking species with strong physique, neat specifications, lively swimming, disease-free and injury-free.

(3) feeding fresh and high quality bait.